Personality might play a big role in how long dogs live. Live fast die young might also apply to dogs, a study in the June issue of The American Naturalist suggests.Vincent Careau, of the University of Sherbrooke in Quebec, Canada, and his colleagues came to that conclusion by comparing numerous dog breeds based on their personalities. For example, poodles are ranked as 29 percent more docile than boxers, and Careau’s team found that poodles are four times more likely than boxers to live past age 10.

Beyond simply looking at aggressiveness, the researchers also found that the most obedient breeds, such as German Shepherds, Poodles, and Bichon Frises, live considerably longer than hard-to-train dogs such as Beagles and Pomeranians. Careau used personality data based on a 1995 psychology study that ranked dog personalities and also compared dogs of similar size.More